Mixed stands of Scots pine (Pinus sylvestris L.) and Norway spruce [Picea abies (L.) Karst] can be more productive than monocultures. Evidence from over 100 years of observation of long-term experiments

Kamil Bielak, Małgorzata Dudzińska, Hans Pretzsch


Aim of study: The objective of this study was to analyse the effect of species mixing of Scots pine and Norway spruce on the productivity at the stand and species level. We also analysed to what extent the mixing effects is modified by drought stress.

Area of study: The study was conducted inN-E Poland and based on three experiments located in Maskulińskie, Strzałowo and Kwidzyn Forest Districts.

Material and methods: We evaluated long-term mixed-species experiments in Scots pine and Norway spruce which are under continuous survey since more than 100 years. Stand productivity was analysed based on the periodic annual increment and total yield of stem volume. Growth and yield were compared between mixed and neighbouring pure stands. As a substitute for the missing Norway spruce monocultures, we used appropriate yield table data. In order to characterize the effect of water supply on the mixing effects, we correlated the Martonne index of aridity with the ratio of Scots pine growth in mixed versus pure stands.

Main results: We found that the mixed stands exceed the weighted mean of the pure stands’ volume productivity on average by 41%. At the species level Scots pine benefits from the mixture by 34% and Norway spruce by 83%. Growth periods with harsh climate conditions reinforce overyielding, while periods with mild conditions reduce the benefit of mixing. The overyielding of mixed stands, especially when growing under unfavourable conditions, is explained by niche complementarity of both species and discussed in view of the stress-gradient-hypothesis.

Research highlights: The revealed overyielding of mixed compared with neighbouring pure stands, particularly under harsh weather conditions, substantiates the preferences of Scots pine-Norway spruce mixtures regarding climate change.    

Keywords: drought resilience; mixed stand; pure stand; facilitation; competition; overyielding; underyielding.

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Akaike H, 1974. A new look at the statistical identification model. IEEE. Transactions on Automatic Control 19 (2), 716–723. http://dx.doi.org/10.1109/TAC.1974.1100705

Bequet R, Kint V, Campioli M, Vansteenkiste D, Muys B., Ceulemanset R, 2012. Influence of stand, site and meteorological variables on the maximum leaf area index of beech, oak and Scots pine. Eur J For Res 131(2): 283–295. http://dx.doi.org/10.1007/s10342-011-0500-x

Brown AHF, 1992. Functioning of mixed-species stands at Gisburn N.W. England. In: Cannel et al. (eds.). The Ecology of Mixed-Species Stands of trees. Oxford, UK. 125-150.

Bruchwald A. Dudzińska T, Dudek A, Michalak K, Wróblewski L, 1985. Outline results of studies on the productiveness of spruce-pine stands in North-East Poland. Sylwan 129 (9), 1-12. [In Polish with English summary].

Bruchwald A, Zasada M, 1995. Pine Stand Structure Formation on Permanent Experimental Plots in the Maskulińske Forest District. Sylwan, Poland. 139(3): 67-85. [In Polish with English summary].

Bruchwald A, Dudek A, Michalak K, Rymer-Dudzińska T, Wróblewski L, Zasada M, 1999. A growth model for spruce stands. Model wzrostu dla drzewostanów świerkowych. Sylwan, Poland. 143(1): 19-31. [In Polish with English summary].

Brzeziecki B, Kienast F, 1994. Classifying the life-history strategies of trees on the basis of the Grimian model. For Ecol Manage 69 (1-3), 1675-187.

Condés S, Del Rio M, Sterba H, 2013. Mixing effect on volume growth of Fagus sylvatica and Pinus sylvestris is modulated by stand density? For Ecol Manage 292, 86-95.

Czuraj M, 1990. Tablice zasobności i przyrostu drzewostanów. Polish yield tables. Tables for Norway spruce by Schwappach (1943), I-V site classes. PWRiL. Warszawa, Poland.

Dudzińska M, Bruchwald A, 2008. The importance and practical possibilities of use of findings of the research carried out in oak stands on permanent sample plots established by Schwappach and Wiedemann. Papers of the Forest Research Institute in Warsaw, Poland. 99 pp. [In Polish with English summary].

Erteld W, 1958. Badania na stałych leśnych powierzchniach doświadczalnych i ich znaczenie dla polsko-niemieckiej współpracy naukowej. Sylwan, Poland. 102(10): 19-24.

Forrester ID, 2014. The spatial and temporal dynamics of species interactions in mixed-species forests: From pattern to process. For Ecol Manage 312, 282-292.

Gamfeldt L, Snäll T, Bagchi R, Jonsson M, Gustafsson L, Kjellander P, et al. 2013. Higher levels of multiple ecosystem services are found in forests with more tree species. Nature Comm 4: 1340. http://dx.doi.org/10.1038/ncomms2328

Harper JL, 1977. Population Biology of Plants. Academic Press, 892 pp.

Hector A, Bagchi R, 2007. Biodiversity and ecosystem multifunctionality. Nature 448, 188-190. http://dx.doi.org/10.1038/nature05947

Jones HE, McNamara N, Mason WL, 2005. Functioning of mixed species stands: evidence from a long-term forest experiment. In: Scharer-Lorenzen M., Körner Ch., Schulze E.-D (eds.). Forest Diversity and Function. Ecological Studies 176. Springer, 111-130.

Jonsson B, 1962. Yield of mixed coniferous forests. Reports of the Forest Research Institute of Sweden 50 (8), 143 pp. [In Swedish with English summary].

Jonsson B, 2001. Volume yield to mid-rotation in pure and mixed sown stands of Pinus sylvestris and Picea abies in Sweden. Studia Forestalia Suecica No. 211, 1-19.

Kelty MJ, 1992. Comparative productivity of monocultures and mixed stands. In: Kelty M.J., Larson B.C., Oliver C.D. (eds.). The Ecology and Silviculture of Mixed-Species Forests; Dordrecht: Kluwer, 125-141. http://dx.doi.org/10.1007/978-94-015-8052-6_8

Lindén M, Agestam E, 2003. Increment and Yield in Mixed and Monoculture Stands of Pinus sylvestris and Picea abies Based on an Experiment in Southern Sweden. Scand J For Res 18: 155-162. http://dx.doi.org/10.1080/02827580310003722

Martonne de E, 1926. Une novelle fonction climatologique: L'indice d'aridité. La Météorologie 21: 449-458.

Mason WL, Connolly T, 2014. Mixtures with spruce species can be more productive than monocultures: evidence from the Gisburn experiment in Britain. Forestry, 87 (2): 209-217. http://dx.doi.org/10.1093/forestry/cpt042

Matheron G, 1963. Principles of geostatistics. Econ. Geology 58: 1246-1266. http://dx.doi.org/10.2113/gsecongeo.58.8.1246

Modrzyński J, 2007. Ecology. In: Tjoelker M.G., Boratynski A., Bugala W., (eds.). Biology and Ecology of Norway Spruce. Springer, 195-220.

Morin X, Fahse L, Scherer-Lorenzen M, Bugmann H, 2011. Tree species richness promotes productivity in temperate forests through strong complementarity between species. Ecol. Lett. 14: 1211-1219. http://dx.doi.org/10.1111/j.1461-0248.2011.01691.x

Olsthoorn AFM, Bartelink HH, Gardiner JJ, Pretzsch H, Hekhuis HJ, Franc A, 1999. Management of mixed-species forest: Silviculture and economics. IBN Scientific Contributions 15, 389 pp.

Pinheiro J, Bates D, DebRoy S, Sarkar D, and the R Development Core Team, 2013. Nlme: Linear and Nonlinear Mixed Effects Models. R package version 3.1–109.

Piotto D, 2008. A meta-analysis comparing tree growth in monocultures and mixed plantations. For Ecol Manage 255: 781-786.

Pirogowicz T, 1978. Wpływ trzebieży na strukturę i przyrost miąższości drzewostanów sosnowych. Einfluss der Durchforstung auf die Struktur und den Zuwachs von Kieferbeständen. Prace IBL 537-541, 147-155. [In Polish with German summary].

Pirogowicz T, 1983. Wpływ trzebieży na produkcyjność i strukturę drzewostanów sosnowych na przykładzie stałych powierzchni doświadczalnych położonych w nadleśnictwach Ruciane, Krutyń i Ryjewo. Einfluss der Durchforstung auf die Produktivität und Struktur von Kieferbeständen im Ruciane, Krutyń und Ryjewo Forstamts. Prace IBL 621/625, 3-38. [In Polish with German summary].

Pirogowicz T, 1990. Produkcyjność drzewostanów sosnowych podsadzonych bukiem w Strzałowie i Polnicy. Produktivität von Kieferbeständen waterpflantz mit Buchen in Strzałowo und Polnica. Prace IBL 721, 86-101. [In Polish with German summary].

Pokorný R, Stojnič S, 2012. Leaf area index of Norway spruce stand in relation to its age and defoliation. – Beskydy 5 (2), 173–180. http://dx.doi.org/10.11118/beskyd201205020173

Pretzsch H, 2005. Diversity and Productivity in Forests: Evidence from Long-Term Experimental Plots. In: Scharer-Lorenzen M., Körner Ch., Schulze E.-D (eds.). Forest Diversity and Function. Ecological Studies 176. Springer, 41-64.

Pretzsch H, 2009. Forest dynamics, growth and yield. From measurement to model, Springer, Berlin, Heidelberg, Germany. 671 pp.

Pretzsch H, Block J, Dieler J, Dong PH, Kohnle U, Nagel J, Spellmann H, Zingg A. 2010. Comparison between the productivity of pure and mixed stands of Norway spruce and European beech along an ecological gradient. Ann. Forest. Sci. 67.

Pretzsch H. Bielak K, Block J, Bruchwald A, Dieler J, Ehrhart H-P, Kohnle U, Nagel J, Spellmann H, Zasada M, Zingg A, 2013a. Productivity of pure versus mixed stands of oak (Quercus petraea (MATT.) LIEBL. and Quercus robur L.) and European beech (Fagus sylvatica L.) along an ecological gradient. Eur J For Res 132(2): 263-280. http://dx.doi.org/10.1007/s10342-012-0673-y

Pretzsch H, Bielak K, Bruchwald A, Dieler J, Dudzińska M, Ehrhart HP, Jensen AM, Johannsen VK, Kohnle U, Nagel J, Spellmann H, Zasada M, Zingg A, 2013b. Mischung und Produktivität von Waldbeständen. Ergebnisse langfristiger ertragskundlicher Versuche, Allg. Forst. Jagdztg. 184: 177-196.

Pretzsch H, Schütze G, Uhl E, 2013c. Resistance of European tree species to drought stress in mixed versus pure forests: evidence of stress release by inter-specific facilitation. Plant Biology 15: 483-495. http://dx.doi.org/10.1111/j.1438-8677.2012.00670.x

Pretzsch H, Biber P, Schütze G, Bielak K, 2014. Changes of forest stand dynamics in Europe. Facts from long-term observational plots and their relevance for forest ecology and management. For Ecol Manage 316: 65-77.

Pukkala T, Vettenranta J, Kolström T, Miina J, 1994. Productivity of mixed stands of Pinus sylvestris and Picea abies. Scand J For Res 9: 143-153. http://dx.doi.org/10.1080/02827589409382824

Quan C, Han S, Utescher T, Zhang C, Liu YS, 2013. Validation of temperature–precipitation based aridity index: Paleoclimatic implications. Palaeogeography, Palaeoclimatology, Palaeoecology 386: 86-95. http://dx.doi.org/10.1016/j.palaeo.2013.05.008

R Core Team, 2014. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. Available in http://www.Rproject.org. [14 February 2014].

Reineke LH, 1933. Perfecting a stand-density index for even-aged forests. J Agr Res 46: 627-638.

Rubner K, 1960. Die pflanzengeographischen Grundlagen des Waldbaues. Neumann Verlag, Radebeulu. Berlin, Germany. 620 pp.

Rötzer T, Seifert T, Gayler S, Priesack E, Pretzsch H, 2012. Effects of Stress and Defence Allocation on Tree Growth: Simulation Results at the Individual and Stand Level. In: Matyssek et al. (eds.). Growth and Defence in Plants: Resource Allocation at Multiple Scales. Ecological Studies 220. Springer-Verlag Berlin Heidelberg, Germany. 401-432. http://dx.doi.org/10.1007/978-3-642-30645-7_18

Ryan EA, Alexander IJ, 1992. Mycorrhizal aspects of improved growth of spruce when grown in mixed stands on heathland soils. In Mycorrhizas in Ecosystems. Read, D.J., Lewis, D.H., Fitter, A.H. and Alexander, I.J. (eds). CAB International, pp. 237–245.

Schmidt A, 1971. Wachstum und Ertrag der Kiefer auf wirtschaftlich wichtigen Standorteinheiten der Oberpfalz. Forstl Forschungsber München, Germany. 1, 187 pp.

Schmidt-Vogt H, 1991. Die Fichte. Band II/3. Verlag Paul Parey, Hamburg, Berlin, Germany. 804 pp.

SILP - Forest Information System in Poland. 2014. Query used for estimation of Scots pine – Norway spruce mixed stands area in Poland (occurrence at the same layer: Scots pine ≥ 40% ∩ Norway spruce ≥ 20% ∩ other tree species ≤ 20%, share by number of individuals of trees species estimated by eye and area in young forest until 20 years old).

Spiecker H, 2000. Growth of Norway spruce (Picea abies (L.) H.Karst) under changing Environmental Conditions in Europe. In: Klimo et al. Spruce Monocultures in Central Europe – Problems and Prospects. EFI Procedings No. 33: 11-26.

Szymański S, 2007. Silviculture of Norway Spruce. In: Tjoelker M.G., Boratynski A., Bugala W., (eds.). Biology and Ecology of Norway Spruce. Springer, 295-308.

Szymkiewicz B, 1966. Tablice zasobności i przyrostu drzewostanów. Polish yield tables. Tables for Norway spruce by Schwappach (1943), I-V site classes. PWRiL Warszawa. Poland.

Schwappach A, 1943. Tables for Norway spruce, I-V site classes. In: Szymkiewicz B. (ed.). Polish yield tables. PWRiL Warszawa. Poland.

Trampler T, 1958. Znaczenie stałych powierzchni doświadczalnych dla gospodarki leśnej w Polsce. Die Bedeutung ständiger Versuchsflächen für die Forstwirtschaft in Polen. Sylwan, Poland. 10: 25-30.

Wiedemann E, 1942. Der gleichaltrige Fichten-Buchen-Mischbestand. Mitt. Forstwirtsch. u. Forstwiss. 13: 1–88.

Wiedemann E, 1943. Der Vergleich der Massenleistung des Mischbestandes mit dem Reinbestand. AFJZ 119: 123 –132.

Wiedemann E, 1951. Ertragskundliche und waldbauliche Grundlagen der Forstwirtschaft. JD Sauerländer's Verlag, Frankfurt am Main.

Zhang Y, Chen H Y H, Reich P B. 2012. Forest productivity increases with eveness, species richness and trait variation: a global metaanalysis, Journal of Ecology,100(3): 742-749. http://dx.doi.org/10.1111/j.1365-2745.2011.01944.x

Zielony R, Kliczkowska A, 2012. Regionalizacja przyrodniczo-leśna polski 2010. Centrum Informacyjne Lasów Państwowych. Warszawa, Poland. 356, Polish nature-geographic regionalization of forests 2010.

Zuur AF, Ieno EN, Walker NJ, Saveliev AA, Smith GM, 2009. Mixed Effects Models and Extensions in Ecology with R. Springer, 574 pp. http://dx.doi.org/10.1007/978-0-387-87458-6

Żybura H, 1990. The forest-forming role of Norway spruce (Picea abies L. Karst.) in Poland with emphasis on the lowland region. SGGW-AR, Warszawa, Poland. 90 pp. [in Polish with English summary].

DOI: 10.5424/fs/2014233-06195

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